Leaders of the European Union’s 27 member states will discuss migration and the bloc’s economic worries at the second day of an EU summit in Brussels on Friday. On Thursday, the assembled prime ministers and presidents agreed to call for a ceasefire in Gaza, to use the revenues of seized Russian assets to help Ukraine, to bolster Europe’s defence industry, and to open accession negotiations with Bosnia-Herzegovina. Friday’s meeting will take a broader view of the bloc’s economic condition and the difficulty of controlling its external borders. Leaders of countries using the Euro single currenc…